Repopulate a recordset from a Dropdown

I've got a dropdownlist on my page that is loaded from a table with names and values.  What I want to do, is when a user selects an item from the drop down, I want the recordset to repopulate and show results in a related table = to that of the dropdown.  I'm pasting my code in as help in understanding the question.

From webform1.aspx.vb -----------------
ublic Class WebForm1
    Inherits System.Web.UI.Page

#Region " Web Form Designer Generated Code "

    'This call is required by the Web Form Designer.
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.SqlConnection1 = New System.Data.SqlClient.SqlConnection
        Me.SqlDataAdapter1 = New System.Data.SqlClient.SqlDataAdapter
        Me.SqlSelectCommand1 = New System.Data.SqlClient.SqlCommand
        Me.DataSet11 = New support.micro_gen.net.DataSet1
        Me.SqlDataAdapter2 = New System.Data.SqlClient.SqlDataAdapter
        Me.SqlSelectCommand2 = New System.Data.SqlClient.SqlCommand
        Me.DataSet21 = New support.micro_gen.net.DataSet2
        CType(Me.DataSet11, System.ComponentModel.ISupportInitialize).BeginInit()
        CType(Me.DataSet21, System.ComponentModel.ISupportInitialize).BeginInit()
        '
        'SqlConnection1
        '
        Me.SqlConnection1.ConnectionString = "workstation id=""*****"";packet size=4096;user id=*********;data source=""mgse" & _
        "rver.micro-gen.net\websql"";persist security info=True;initial catalog=MicroGenSu" & _
        "pport;password=************"
        '
        'SqlDataAdapter1
        '
        Me.SqlDataAdapter1.SelectCommand = Me.SqlSelectCommand1
        Me.SqlDataAdapter1.TableMappings.AddRange(New System.Data.Common.DataTableMapping() {New System.Data.Common.DataTableMapping("Table", "tbl_cemetary", New System.Data.Common.DataColumnMapping() {New System.Data.Common.DataColumnMapping("PrimaryKey", "PrimaryKey"), New System.Data.Common.DataColumnMapping("Name", "Name"), New System.Data.Common.DataColumnMapping("Address", "Address"), New System.Data.Common.DataColumnMapping("Township", "Township"), New System.Data.Common.DataColumnMapping("County", "County"), New System.Data.Common.DataColumnMapping("State", "State"), New System.Data.Common.DataColumnMapping("ZipCode", "ZipCode"), New System.Data.Common.DataColumnMapping("GPSNorth", "GPSNorth"), New System.Data.Common.DataColumnMapping("GPSWest", "GPSWest"), New System.Data.Common.DataColumnMapping("GPSElevation", "GPSElevation"), New System.Data.Common.DataColumnMapping("CemURL", "CemURL")})})
        '
        'SqlSelectCommand1
        '
        Me.SqlSelectCommand1.CommandText = "SELECT PrimaryKey, Name, Address, Township, County, State, ZipCode, GPSNorth, GPS" & _
        "West, GPSElevation, CemURL FROM tbl_cemetary ORDER BY Name"
        Me.SqlSelectCommand1.Connection = Me.SqlConnection1
        '
        'DataSet11
        '
        Me.DataSet11.DataSetName = "DataSet1"
        Me.DataSet11.Locale = New System.Globalization.CultureInfo("en-US")
        '
        'SqlDataAdapter2
        '
        Me.SqlDataAdapter2.SelectCommand = Me.SqlSelectCommand2
        Me.SqlDataAdapter2.TableMappings.AddRange(New System.Data.Common.DataTableMapping() {New System.Data.Common.DataTableMapping("Table", "tbl_cemdata", New System.Data.Common.DataColumnMapping() {New System.Data.Common.DataColumnMapping("LastName", "LastName"), New System.Data.Common.DataColumnMapping("FirstName", "FirstName"), New System.Data.Common.DataColumnMapping("DoB", "DoB"), New System.Data.Common.DataColumnMapping("DoD", "DoD"), New System.Data.Common.DataColumnMapping("Comment", "Comment"), New System.Data.Common.DataColumnMapping("PrimaryKey", "PrimaryKey")})})
        '
        'SqlSelectCommand2
        '
        'This is where my Recordset should select the value of the dropdown list.
        Me.SqlSelectCommand2.CommandText = "SELECT LastName, FirstName, DoB, DoD, Comment, PrimaryKey FROM tbl_cemdata WHERE " & _
        "(PrimaryKey = 7)"

        Me.SqlSelectCommand2.Connection = Me.SqlConnection1
        '
        'DataSet21
        '
        Me.DataSet21.DataSetName = "DataSet2"
        Me.DataSet21.Locale = New System.Globalization.CultureInfo("en-US")
        CType(Me.DataSet11, System.ComponentModel.ISupportInitialize).EndInit()
        CType(Me.DataSet21, System.ComponentModel.ISupportInitialize).EndInit()

    End Sub
    Protected WithEvents SqlConnection1 As System.Data.SqlClient.SqlConnection
    Protected WithEvents SqlDataAdapter1 As System.Data.SqlClient.SqlDataAdapter
    Protected WithEvents DataSet11 As support.micro_gen.net.DataSet1
    Protected WithEvents DropDownList1 As System.Web.UI.WebControls.DropDownList
    Protected WithEvents SqlSelectCommand1 As System.Data.SqlClient.SqlCommand
    Protected WithEvents SqlDataAdapter2 As System.Data.SqlClient.SqlDataAdapter
    Protected WithEvents SqlSelectCommand2 As System.Data.SqlClient.SqlCommand
    Protected WithEvents DataSet21 As support.micro_gen.net.DataSet2
    Protected WithEvents DataGrid1 As System.Web.UI.WebControls.DataGrid

    'NOTE: The following placeholder declaration is required by the Web Form Designer.
    'Do not delete or move it.
    Private designerPlaceholderDeclaration As System.Object

    Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
        'CODEGEN: This method call is required by the Web Form Designer
        'Do not modify it using the code editor.
        InitializeComponent()
    End Sub

#End Region

    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'Put user code to initialize the page here
        If Not IsPostBack Then
            SqlDataAdapter1.Fill(DataSet11)
            DropDownList1.DataBind()
        End If
        SqlDataAdapter2.Fill(DataSet21)
        DataGrid1.DataBind()

    End Sub

End Class
--------------------------------------------

From webform1.aspx -------------------------
<%@ Page Language="vb" AutoEventWireup="false" Codebehind="WebForm1.aspx.vb" Inherits="support.micro_gen.net.WebForm1"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
      <HEAD>
            <title>WebForm1</title>
            <meta name="GENERATOR" content="Microsoft Visual Studio .NET 7.1">
            <meta name="CODE_LANGUAGE" content="Visual Basic .NET 7.1">
            <meta name="vs_defaultClientScript" content="JavaScript">
            <meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5">
      </HEAD>
      <body MS_POSITIONING="GridLayout">
            <form id="Form1" method="post" runat="server">
                  <asp:DropDownList id=DropDownList1 style="Z-INDEX: 101; LEFT: 16px; POSITION: absolute; TOP: 16px" runat="server" Width="192px" DataSource="<%# DataSet11 %>" DataValueField="PrimaryKey" DataTextField="Name" AutoPostBack="True">
                  </asp:DropDownList>
                  <asp:DataGrid id=DataGrid1 style="Z-INDEX: 102; LEFT: 16px; POSITION: absolute; TOP: 64px" runat="server" Width="832px" DataSource="<%# DataSet21 %>" BorderColor="#CCCCCC" BorderStyle="None" BackColor="White" CellPadding="3" BorderWidth="1px" DataKeyField="PrimaryKey" AllowSorting="True" Font-Size="Small" Height="96px">
                        <FooterStyle ForeColor="#000066" BackColor="White"></FooterStyle>
                        <SelectedItemStyle Font-Bold="True" ForeColor="White" BackColor="#669999"></SelectedItemStyle>
                        <ItemStyle Font-Size="X-Small" ForeColor="#000066"></ItemStyle>
                        <HeaderStyle Font-Size="Smaller" Font-Bold="True" ForeColor="White" BackColor="#006699"></HeaderStyle>
                        <Columns>
                              <asp:BoundColumn DataField="LastName" HeaderText="Last Name"></asp:BoundColumn>
                              <asp:BoundColumn DataField="FirstName" HeaderText="First Name"></asp:BoundColumn>
                              <asp:BoundColumn DataField="DoB" HeaderText="Date of Birth"></asp:BoundColumn>
                              <asp:BoundColumn DataField="DoD" HeaderText="Date of Death"></asp:BoundColumn>
                              <asp:BoundColumn DataField="Comment" HeaderText="Comments"></asp:BoundColumn>
                        </Columns>
                        <PagerStyle HorizontalAlign="Left" ForeColor="#000066" BackColor="White" Mode="NumericPages"></PagerStyle>
                  </asp:DataGrid>
            </form>
      </body>
</HTML>
------------------------------------

I'm using Visual studio.net 7.1